High mount center light LED
 

Hi my high mount center brake light, have dark spot in the center, 2 led are not working how do i fix this problem, and where do i get the led from and what voltage are they...........:nanana:

Same problem here. Anybody know?

The service manual says the whole assembly needs to be replaced, but only one ~3 inch segment is dark on mine and I'd prefer to repair it.

Especially because the part is $240+, vs. a bulb or fixing the circuit board.
Genuine BMW Third Brake Light Assembly 63258362039 - Free Shipping

I've already removed the light assembly, which is straightforward in the service manual (and way more involved than expected - step one is to remove the spoiler).

Fixed!

Here's some info, and what I did. My car is a 2001 x5, and x3's and later x5's are different in this area, but I will guess similar enough that this info will help. Based on the June 2001 manufacturing date on the unit, I'm sure this part is original, with 174k miles.

It's a plastic-welded unit, not intended for disassembly or repair, just replacement.

The LEDs run off 2.3V each, powered in clusters of 4, all soldered to a single circuit board running the full width of the assembly. Red LEDs, then a clear (white) lens, then a red outer lens.

The whole assembly is powered with 12V on the blue wire, ground on the brown wire.

Symptoms - one segment of 4 LEDs was out, the rest all worked fine. It appears that with this circuit design, when any one LED fails in any way it will take out the entire 4-LED segment.

Root cause - failed solder joint on one of the LEDs.

Solution - After checking voltages on working-vs-non-working segments and understanding the circuit, I figured it could be a bad joint and I had nothing to lose, so I just started re-flowing the solder on the joints in that part of the circuit. Luckily the very first joint I hit was the problem and it lit up. I continued to re-flow all 4 joints on that LED, for good measure.

Hardest part - disassembly of the plastic-welded light assembly. Not really hard, but I did not know how it would go, and it took some time and care to do it nicely. I used a thin Dremel cutoff tool around the entire outer seam (between the red lens and gray plastic housing). Then used a Dremel small cutting tool to cut the 4 plastic ~rivet type moldings off.

I used a 12V cordless tool (Craftsman Nextec) battery to provide 12V for testing throughout.

First step - removing the light assembly from the car: remove spoiler = open hatch, remove 2 rubber plugs near the spoiler, remove 5 Torx T30 screws (2 of them under the rubber plugs) holding it on, remove carefully. Then just 2 Philips #2 screws holding the light assembly in place, one connector with 12V/ground.

Here's a photo showing it disassembled, after the repair, with some of the tools.
Attachment 68154